You seem to not be depending on “@angular/core”. This is an error
Just remove the node_modules folder, then re-install. ``` rm -ref node_modules cnpm i
ng server
## after have a try above code, you will get the following
![](http://images2017.cnblogs.com/blog/1108876/201712/1108876-20171207060719066-1994628413.png)